JP3300943B2 - Synthetic resin sheet material for molded containers and molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding material for a container formed by bulging a sheet material made of a synthetic resin, which is generally known for packaging foods or small articles of small goods, and a container made of the molding material. TECHNICAL FIELD The present invention relates to a molded article, which is excellent in heat resistance, cold resistance, and weather resistance and has good workability as compared with the related art, and is a recyclable synthetic resin sheet material for a molded container as before.

[0002]

2. Description of the Related Art A conventional packaging container formed by bulging such a synthetic resin sheet material is generally known as follows.
Using a synthetic resin sheet as a material, a predetermined shape is given by blow molding. The synthetic resin sheet used for such a purpose may be any type of synthetic resin sheet as long as it can be deformed by heat, but with a certain degree of mechanical strength and withstands a wide range of temperature changes, Because it is required to be scientifically stable and inexpensive in terms of productivity and material costs, conventionally, PET (polyethylene terephthalate resin), PP
(Polypropylene resin), PE (polyethylene resin),
PC (polycarbonate resin) and the like are frequently used.

[0003]

The above-mentioned materials for packaging containers are, in the case of a material sheet composed of each single substance, a material having a low softening point and good workability, which has low heat resistance and has a rectangular shape at high temperatures. It has the disadvantage of lacking stability and low mechanical strength.On the other hand, materials with excellent heat resistance have a high softening point and poor workability, and materials with high hardness are fragile, such as cracking at low temperatures. Had a problem to be solved.

[0004] Therefore, the present inventor, when producing the above-described packaging container, has heat resistance, cold resistance,
A synthetic resin sheet material for molded containers, which has excellent weather resistance, has good processability, is inexpensive, realizes a reduction in packaging costs, and can be recycled like conventional materials.
An object of the present invention is to provide a molded article such as a container having excellent temperature characteristics, robustness, and workability by using the synthetic resin sheet material.

[0005]

The structure of a synthetic resin sheet material for a molded container for achieving the above object will be described with reference to claims 1 to 3. The molded container according to claim 1 of the present invention. The synthetic resin sheet material is made of a composite synthetic resin in which a fibrous substance 2 is mixed with a polyethylene terephthalate resin 1. Further, the synthetic resin sheet material for a molded container according to claim 2 has a surface layer made of a polyolefin resin on both surfaces of a core layer P made of a composite synthetic resin in which a fibrous substance 2 is mixed with a polyethylene terephthalate resin 1. 3,3 '
Are laminated. Further, the synthetic resin sheet material for a molded container according to claim 3 has a surface layer 3 made of a composite material obtained by mixing a fibrous substance 2 with a polyethylene terephthalate resin 1 on both surfaces of a core layer P ′ made of a polycarbonate resin. ,
3 'are stacked. Further, the invention based on the tenth to twelfth aspects is a molded product obtained by heating and softening the synthetic resin sheet material for a molded container according to the first to third aspects and bulging it into a predetermined shape.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In carrying out the present invention,
The synthetic resin sheet material for a molding container according to claim 1, wherein the polyethylene terephthalate resin 1 in a pellet form and the fibrous substance 2 are mixed together and extruded into a sheet by an extruder, whereby a molded article C is consistently obtained. Is sent to the blow molding process. The fibrous substance 2 to be mixed has a thickness of 500 to 1
Using polyethylene terephthalate (polyester) fiber cut to a length of 5 to 15 mm with 000 denier,
Practically, it is only necessary to cut and use the lint of the polyester fiber. The material of the fibrous substance 2 is not limited to the polyester fiber, but by mixing fibers of the same quality as the polyethylene terephthalate resin 1 which acts as a binder like the polyester fiber, the weather resistance is higher than that of the polyethylene terephthalate resin alone. Heat resistance is improved and workability is also improved. When the thickness of the fibrous substance 2 is smaller than the above range, the fibrous substance 2 is fused with the mixed polyethylene terephthalate resin, and the mixing effect is diminished. When the thickness is large, extrusion into a sheet becomes difficult. If the overall size, such as the thickness and length, of the fibrous substance 2 is within the above range, the sheet passes through the extruder without any problem when it is processed into a sheet by the extruder, and the conventional ordinary extruder is used. Can be used without hindrance.

In the synthetic resin sheet material for a molded container according to the second aspect, the core layer P is extruded and formed in the same manner as the synthetic resin sheet material for a molded container according to the first aspect. The polyolefin resin is extruded in layers on both the front and back surfaces of the layer P to form the surface layers 3 and 3 'to form a layered structure.
The polyolefin resin used as the surface layers 3 and 3 'may be a commonly used polyethylene resin, polypropylene resin, or the like, but the polyethylene resin has a softening point as low as about 100 degrees when the transparency is low and the density is low. Although processing is easy, hardness, strength, heat resistance are inferior, and it may be deformed in a high temperature environment, but compensate for the disadvantage that polyethylene terephthalate resin which is the core material tends to crack at low temperature. I have. In the case of high density, the softening point is around 120 degrees, and the hardness, strength,
Somewhat superior in heat resistance. Further, the polypropylene resin has a higher softening point than the polyethylene resin, and is excellent in hardness, mechanical strength and heat resistance.

What kind of polyolefin resin is used as the above-mentioned surface layers 3 and 3 'is appropriately selected and selected according to the purpose of use of the molded article C produced from the synthetic resin sheet material for the molded container. Should be used. Further, the materials of the surface layers 3 and 3 'need not be the same kind of synthetic resin as described in claim 5 or 6. The interior of the molded article may be a polypropylene resin and the exterior may be a polyethylene resin, or vice versa. Such an embodiment shows intermediate properties in terms of various properties such as hardness, strength, heat resistance and the like when compared with the case where the surface layers 3 and 3 ′ are the same kind of synthetic resin. The material to be finely combined is selected according to the conditions, and a molded product having desired performance can be obtained.

The synthetic resin sheet material for a molded container according to the third aspect of the present invention comprises a polyethylene terephthalate resin 1 and a fibrous substance 2 on both surfaces of a core layer P made of a polycarbonate resin.
Are laminated on the surface layers 3 and 3 ′ made of a composite material in which is mixed. The production means is the same as the synthetic resin sheet material for a molded container described in claim 2 described above.

The completed synthetic resin sheet material for a molded container is as follows:
As in the conventional case, a molded product is formed by processing means such as blow molding. When molded products are mass-produced in a very large amount and at a high speed, such as egg packaging containers and miso containers, the sheet material extruded from the extruder is directly and continuously circulated to an automatic molding machine in which a molding die is circulated. It is conveyed and the molded product is output. The molding conditions in the automatic molding machine are set so as to be suitable for the structure of the synthetic resin sheet material for the molding container, so it is possible to produce molded products of any kind and properties with high efficiency. .

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below based on an embodiment shown in the drawings. 1 is an enlarged perspective view of a first embodiment of the present invention, FIG. 2 is an enlarged perspective view of a second embodiment, FIG. 3 is an enlarged perspective view of a third embodiment, and FIG. 4 is an enlarged perspective view of a fourth embodiment. FIG. 5 is a perspective view showing the shape of a molded product corresponding to the fifth embodiment, and FIG.
It is a perspective view which shows the shape of the other molded article corresponding to an Example.

FIG. 1 shows the structure of the first embodiment. The first embodiment is a synthetic resin sheet material for a molded container according to claim 2, wherein polyethylene resin is extruded in layers on both the front and back surfaces of the core layer P to form the surface layers 3, 3 '. It has a structure. The core layer P is a polyethylene terephthalate resin 1 and a fibrous substance 2 mixed with polyethylene terephthalate (polyester) fiber lint cut to a thickness of 800 denier and a length of 10 mm. Although illustration is omitted, as a modification of the first embodiment,
There is a sheet in which the surface layers 3, 3 'are replaced with a polypropylene resin. This modified example is characterized in that the heat resistance, weather resistance and mechanical strength are improved as compared with the first embodiment, but the molding temperature is increased.

FIG. 2 shows the structure of the second embodiment. The second embodiment is a synthetic resin sheet material for a molded container according to claim 1, wherein the sheet material is a polyethylene terephthalate resin 1 and a fibrous substance 2 having a thickness of 800 denier and a length of 10 mm. It is made of a material mixed with cut waste of cut polyethylene terephthalate (polyester) fibers. This embodiment is a single-layer sheet made of a composite synthetic resin similar to the core layer P of the first embodiment. Compared to a sheet made of a single material of only polyethylene terephthalate resin, when it is formed into a molded product, the weather resistance, heat resistance, and workability are better.

FIG. 3 shows the structure of the third embodiment. The second embodiment is a synthetic resin sheet material for a molded container having the same structure as the first embodiment, but the materials of the surface layers 3, 3 'are different on the front and back, and one surface layer 3 is made of polyethylene and the other is made of polyethylene. Surface layer 3
'Is polypropylene. The core layer P is the same as in the first embodiment. This embodiment shows intermediate features between the first embodiment and a modification of the first embodiment. Contrary to the above, it goes without saying that the same is true even if the surface layer 3 is made of polypropylene and the surface layer 3 'is made of polyethylene.

FIG. 4 shows the structure of the fourth embodiment. The fourth embodiment is a synthetic resin sheet material for a molded container according to claim 3, wherein the core layer P is made of polycarbonate resin.
'On both surfaces, a surface layer 3 made of a composite synthetic resin in which a fibrous substance 2 is mixed with a polyethylene terephthalate resin 1
3 ′ has a three-layer structure in which the layers are stacked.

FIG. 5 shows the shape of the fifth embodiment. This embodiment is an example of a molded article C using the synthetic resin sheet material for a molded container disclosed in the above-mentioned various embodiments. The molded article of the fifth embodiment is a container for packaging eggs, and the molding material is the polyethylene terephthalate resin 1 and the fibrous substance 2 described in the first embodiment, having a thickness of 800 denier and a length of 10%.
A three-layer structure in which polyethylene resin is extruded into layers on both front and back surfaces of a core layer P made of a composite synthetic resin mixed with lint of polyethylene terephthalate (polyester) fiber cut into mm to form surface layers 3, 3 '. Uses structured sheet material.

FIG. 6 shows the shape of the sixth embodiment. This embodiment is another example of a molded product C using a synthetic resin sheet material for a molded container, and is a container for packaging miso. The molding material is the synthetic resin sheet material for a molding container described as the second embodiment.

Although the embodiments which are considered to be representative of the present invention have been described above, the present invention is not necessarily limited to only the structures of these embodiments, but includes the structural requirements according to the present invention, and refers to the present invention. The present invention can be implemented by appropriately modifying it within the range of achieving the object and having the following effects.

[0019]

As is clear from the above description, the synthetic resin sheet material for a molding container in the present invention is a sheet made of a composite synthetic resin in which a fibrous substance is mixed with a polyethylene terephthalate resin, or a polyethylene terephthalate. Since it is a composite material sheet in which a surface layer made of a polyethylene resin or a polypropylene resin is laminated on both front and back surfaces of an intermediate layer made of a composite synthetic resin in which a fibrous substance is mixed with a resin 1, a polyethylene terephthalate resin which has been frequently used (PET) Compared to a sheet of a single component, the sheet has excellent properties such as heat resistance, cold resistance, and weather resistance, and has good workability. Therefore, molded products such as eggs packaging containers manufactured using the sheet are also excellent in performance such as heat resistance, cold resistance and weather resistance.

Further, by selecting the kind and combination of the resin forming the intermediate layer and the surface layer, the above-mentioned properties such as heat resistance, cold resistance and weather resistance can be adjusted according to the use of the molded article. . In addition, the material is not special and therefore very inexpensive. Therefore, the cost of the molded article can be reduced in combination with the good workability. Furthermore, in a sheet made of a composite synthetic resin in which a fibrous substance is mixed with a polyethylene terephthalate resin, the component is the polyethylene terephthalate resin itself, so that it has the effect of being able to be recycled like conventional materials. is there.

[Brief description of the drawings]

FIG. 1 is an enlarged perspective view of a first embodiment.

FIG. 2 is an enlarged perspective view of a second embodiment.

FIG. 3 is an enlarged perspective view of a third embodiment.

FIG. 4 is an enlarged perspective view of a fourth embodiment.

FIG. 5 is a perspective view of a fifth embodiment.

FIG. 6 is a perspective view of a sixth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polyethylene terephthalate resin 2 Fibrous substance 3, 3 'Surface layer P, P' Core layer C Molded article

Continued on the front page (51) Int.Cl. ⁷ Identification code FI B29K 67:00 B29K 105: 12 105: 12 B29L 7:00 B29L 7:00 9:00 9:00 22:00 22:00 C08L 67:02 C08L 67:02 B29C 67/16

Claims (13)

(57) [Claims] (1) Polyethylene terephthalate resin (1)
A synthetic resin sheet material for a molding container made of a composite synthetic resin mixed with a fibrous substance (2) obtained by cutting lint . 2. Polyethylene terephthalate resin (1)
Surface layers (3) and (3 ') made of polyolefin resin are laminated on both sides of a core layer (P) made of a composite synthetic resin mixed with fibrous material (2) cut from lint Synthetic resin sheet material for molded containers. 3. A core layer made of a polycarbonate resin.
Polyethylene terephthalate resin (1) on both sides of (P ')
A synthetic resin sheet material for a molding container in which surface layers (3) and (3 ') made of a composite synthetic resin mixed with a fibrous substance (2) obtained by cutting lint are laminated. 4. The fibrous substance (2) has a thickness of 500-10.
The synthetic resin sheet material for a molded container according to any one of claims 1 to 3 , wherein the synthetic resin sheet material is a polyethylene terephthalate resin fiber lint having a size of 00 denier and cut to a length of 5 to 15 mm. 5. The synthetic resin sheet material for a molded container according to claim 2, wherein the surface layers (3) and (3 ′) are a polyethylene resin. 6. The synthetic resin sheet material for a molded container according to claim 2, wherein the surface layers (3) and (3 ′) are a polypropylene resin. 7. The synthetic resin sheet material for a molded container according to claim 2, wherein one of the surface layers (3) and (3 ′) is a polyethylene resin and the other is a polypropylene resin. 8. Polyethylene terephthalate resin (1)
Core made of composite synthetic resin mixed with fibrous substance (2)
Molding in which surface layers (3) and (3 ') are laminated on both sides of layer (P)
A synthetic resin sheet material for a container, wherein one of the surface layers (3) and (3 ') is a polyethylene resin and the other is a polyethylene terephthalate resin. 9. Polyethylene terephthalate resin (1)
Core made of composite synthetic resin mixed with fibrous substance (2)
Molding in which surface layers (3) and (3 ') are laminated on both sides of layer (P)
A synthetic resin sheet material for a container, wherein one of the surface layers (3) and (3 ') is a polypropylene resin and the other is a polyethylene terephthalate resin. 10. Polyethylene terephthalate resin (1)
A molded article formed by heating and softening a synthetic resin sheet material made of a composite synthetic resin mixed with a fibrous substance (2) obtained by cutting lint into a predetermined shape. 11. Polyethylene terephthalate resin (1)
Surface layers (3) and (3 ') made of polyolefin resin are laminated on both sides of a core layer (P) made of a composite synthetic resin mixed with fibrous material (2) obtained by cutting lint A molded product obtained by heating and softening a synthetic resin sheet material and bulging it into a predetermined shape. 12. A core layer made of a polycarbonate resin.
Polyethylene terephthalate resin (1) on both sides of (P ')
Synthetic resin sheet material on which surface layers (3) and (3 ') made of a composite synthetic resin mixed with fibrous material (2) obtained by cutting lint are heat-softened and bulged into a predetermined shape. Molded products. 13. A shaped article according to any one of the molded article according to claim 10 to 12 is a packaging container used in the product packaging.